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Cassette Style
DC-DC Converters
Q Series
Edition 5/5.2000
15/25
R-Control for Output Voltage Adjustment
Note: With open R input,
Uo
≈ U
o nom. R excludes option P.
All modules offer a programmable output voltage feature.
The programming is performed either by an external control
voltage
Uext or an external resistor R1 or R2, connected to
the R-input. Trimming is limited to the values given in the
table below (see also:
Electrical Output Data). With a dis-
connected R-input, the output voltage is set to
Uo nom.
Simultaneous use of the R-input function and option P is
not possible. If option P is built-in, the R-input will remain
active but its function must not be used; do not connect pin
R at all!
With double output modules, both outputs are affected by
the R-input settings.
If output voltages are set higher than
Uo nom, the output cur-
rents should be reduced accordingly, so that the maximum
specified output power is not exceeded.
Caution: To prevent damage,
Uext should not exceed
20 V, nor be negative.
a) Adjustment by means of an external control voltage
Uext between R (16) and S– (14). Uo is dependent upon
Uext:
Uo
Uext
Uext ≈ 2.5 V –––––––
Uo ≈ Uo nom –––––
Uo nom
2.5 V
b) Adjustment by means of an external resistor:
The resistor can either be connected between the pins R
(16) and S– (14) to set
Uo
< U
onom, or between the pins R
(16) and S+ (12) to set
Uo
> U
o nom.
Note: R inputs of n units with paralleled outputs may be
paralleled, too, but if only one external resistor is to be
used, its value should be
R1/n, or R2/n respectively.
Fig. 20
Output voltage programming using a control voltage Uext
Load 1
Load 2
Vo2+
Vo1–
Vo2–
S–
S+
Vo1+
Double
output
R
Vi–
Vi+
i
+
Uext
–
06093
Fig. 21
Output voltage programming using R1 or R2
Load 1
R1
R 2
Vo1–
S–
Vo1+
S+
Single
output
R
Vi–
Vi+
i
06094
Table 8a: R1 for Uo < Uo nom; approximate values (Ui nom, Io nom, series E 96 resistors); R2 = ∞
Uo nom = 5.1 V
Uo nom = 12 V
Uo nom = 15 V
Uo nom = 24 V
Uo (V)
R1 [k]
Uo [V] 1
R1 [k]
Uo [V] 1
R1 [k]
Uo [V] 1
R1 [k]
4.0
14.7
5.5
11.0
3.40
16.0
4.53
14.0 2
28.0 2
5.62
4.1
16.5
6.0
12.0
4.02
8.5
17.0
5.23
15.0 2
30.0 2
6.65
4.2
18.2
6.5
13.0
4.75
9.0
18.0
6.04
16.0 2
32.0 2
8.06
4.3
21.5
7.0
14.0
5.62
9.5
19.0
6.98
17.0 2
34.0 2
9.76
4.4
25.5
7.5
15.0
6.65
10.0
20.0
8.06
18.0 2
36.0 2
12.1
4.5
30.1
8.0
16.0
8.06
10.5
21.0
9.31
19.0
38.0
15.4
4.6
37.4
8.5
17.0
9.76
11.0
22.0
11.0
20.0
40.0
20.0
4.7
47.5
9.0
18.0
12.1
11.5
23.0
13.3
20.5
41.0
23.7
4.8
64.9
9.5
19.0
15.4
12.0
24.0
16.2
21.0
42.0
28.0
4.9
97.6
10.0
20.0
12.5
25.0
20.0
21.5
43.0
34.8
5.0
200.0
10.5
11.0
28.0
13.0
26.0
26.1
22.0
44.0
44.2
11.0
22.0
44.2
13.5
27.0
36.5
22.5
45.0
60.4
11.5
23.0
93.1
14.0
28.0
56.2
23.0
46.0
90.9
14.5
29.0
115.0
23.5
47.0
190.0
Table 8b: R2 for Uo
> U
o nom; approximate values (Ui nom, Io nom, series E 96 resistors); R1 =
∞
Uo nom = 5.1 V
Uo nom = 12 V
Uo nom = 15 V
Uo nom = 24 V
Uo [V]
R2 [k]
Uo [V] 1
R2 [k]
Uo [V] 1
R2 [k]
Uo [V] 1
R2 [k]
5.2
215.0
12.2
24.4
931
15.3
30.6
1020
24.5
49.0
1690
5.3
110.0
12.4
24.8
475
15.5
31.0
619
25.0
50.0
866
5.4
75.0
12.6
25.2
316
15.7
31.4
453
25.5
51.0
590
5.5
57.6
12.8
25.6
243
16.0
32.0
316
26.0
52.0
442
5.6
46.4
13.0
26.0
196
16.2
32.4
267
26.4
52.8
374
13.2
26.4
169
16.5
33.0
221
1 First column: single output units or double output units with separated/paralleled outputs, second column: outputs in series connection.
2 For DQ 2660: Uo tr min = 19/38 V.